This invention relates to coke production. In one of its aspects this invention relates to the prevention of environmental pollution. In a concept of the invention means are provided for reducing environmental pollution during operation of discharging coke from an oven in a battery of coke ovens.
In the production of coke from coal for use in making steel, the coal is most often treated in a by-product coke oven. This process along with the equipment involved is described in "The Making, Shaping and Treating of Steel,"9th Edition, 1971, pages 109-164, published by U.S. Steel Corporation. At the end of the carbonization period, hot coke is pushed from one side of the oven through the slot-type door at the other side of the oven into an open railcar. Large quantities of atmospheric pollutants, such as smoke and combustion fumes, are released in the general area of contact between the hot coke and air as the hot coke emerges from the oven and bursts into flame.
Recently, the consideration of environmental quality has required that as much atmospheric pollutants as feasible should be kept from entering the atmosphere. Since most of the batteries of coke ovens already in existence do not have provision for containing the pollutants produced in the discharge of coke from an oven, an important consideration in the design of pollution control equipment is that it can be added to the coke handling equipment already in use.
The equipment associated with discharging a coke oven in a battery of ovens has traditionally been a guide rack on a coke guide carriage which is moved on a track along the battery of ovens by a door machine. The door machine removes the coke oven door on the quenching side of a preselected oven and then moves to position the carriage at the particular oven to be pushed. The oven door is also removed from the opposite side of the same oven from which the coke is pushed through the slot-type door and between the coke guides. These guides are vertical walls braced on the carriage sufficiently close together to aid in retaining the coherence of the coke. As the coke passes from between the guides, the large cake of coke extruded through the door opening is no longer supported at the bottom and sides. The coke crumbles in a fiery mass into an open railway car spotted on a track situated sufficiently below the guide car to catch the discharged coke. An oven discharge can produce a considerable quantity of smokey gas at about 1000.degree. F. initial discharge temperature.
In general, the equipment necessary for removing atmospheric pollutants during the discharge of coke from an oven includes a shielding or hood device for surrounding the discharged material and an induced draft means for withdrawing or exhausting the pollutants together with ambient air from this hood and exhausting the air and pollutants in a closed duct to a removed area where the air carrying the pollutants can be treated to remove the polluting material. By the use of such apparatus as gas scrubbers and separators, the pollutants can be collected and the cleaned air released to the atmosphere.
The present invention concerns a mobile exhaust or collection hood attached to a coke guide carriage adapted for the collection of pollutant containing air at a multiplicity of oven discharge sites along a coke oven battery with means for conducting the collected pollutants into a stationary exhaust manifold header.